This invention relates to a device for the laying of weft yarns between two longitudinal conveyors running towards a knitting needle head of a warp knitting machine. The conveyors are equipped with hooks into which the weft yarns presented by a weft yarn carriage are hooked so that the weft yarns, constituting one weft yarn group, and running towards one of the conveyors are pushed temporarily beneath the hooks of a depressor which can be moved into a depressing position to such an extent that the weft yarns cross the shafts of the hooks.
Such a device is known from DE-OS No. 21 29 866. In this published application, a warp knitting machine is described in which depressors are provided on the weft yarn carrriage, each of said depressors being moved downward at the end of the path of travel of the weft yarn carriage by means of limit stops which are attached to the machine frame. The weft yarns running on a given longitudinal conveyor are thereby pushed down by the depressors to such an extent that the weft yarns cross the shafts of the hooks. When the weft yarn carriage reverses its direction of travel after having reached the end of its path of travel, the depressing action exerted on the weft yarns stops practically immediately following this reversal of travel. Since the depressors are activated only in the end zone of the weft yarn carriage's path of travel this activation is relatively short. Together with this laying of the weft yarns in the longitudinal conveyors, whereby the weft yarns cross the shafts of the hooks of said longitudinal conveyors, an insertion into stationary grasping devices located above the longitudinal conveyors also takes place. It is the role of said grasping devices to hold the yarns during the running of the longitudinal conveyors until said longitudinal conveyors have moved across the width of a weft yarn group, whereupon the yarns are transferred by means of dropping devices from the grasping devices into the free hooks of the longitudinal conveyors located below. The dropping devices consist of depressors swinging from the outside in and take effect when the weft yarn carriage, in its travel away from the longitudinal conveyor concerned has reached approximately the middle between the two longitudinal conveyors.
Furthermore, a device for the laying of weft yarns between two longitudinal conveyors running toward a knitting needle head of a warp knitting machine is known from DE-OS No. 20 12 114 in which, as in the object of DE-OS No. 21 29 866, depressors are installed on the weft yarn carriage and are activated in the same manner and for the same length of time as is the case with the object of DE-OS No. 21 29 866. Also in the device according to DE-OS No. 20 12 114, the insertion of the weft yarns into the hooks of the longitudinal conveyors is accompanied by a hooking into a further element, i.e. into an offset rake which moves counter to the running direction of the longitudinal conveyors up to the adjoining group of free hooks on the longitudinal conveyor and are then shifted together with the longitudinal conveyor, whereby the transfer of the yarns from the offset rake to the hooks of the longitudinal conveyor takes place during this shift because of the appropriate configuration of the offset rake and the hooks. In the device according to DE-OS No. 20 12 114 therefore, the dropping devices provided in the object of DE-OS No. 21 29 866 can be dispensed with.